Means for introducing liquid into flowing fluids



May 6, 1941.

MEANS FOR INTRODUCING `LIQUID INTO FLOWING FLUIDS Filed June 28, 1939 2Sheets-Sheet 1 @www2/13 D. A. sa'lLLfEr-Qs Erm. 2,240,808

Patented May e, v1941 y 2,240,808 -UNITE'D STATES PATENT OFFICE y2,240,80s i l i vMEAN S ISIQUID INT Donald A. Sillerl, Dallas, andAlexander Clarke,

Coleman, Tex.; said Clarke rassignor to said Sillon Application June za.1939, sex-lai No. 281,696

s claim. (ci. reines) This invention relates -'to new and usefulimprovements in means for introducing liquid intol ilowing fluids. t

The inventionlparticularly lhas to do with the introduction of anodorizing liquid into a con-,- lined ilowi'ng-stream of gas so .as toimpart a .distinctive and recognizable odor to said gas.

Y within the lay-pass line, whereby variations in y The usual type ofvdevices and apparatus which are in general use, for this purpose, arerpon sive to variations in the velocltygof gas flow,

through the ilow line, but are not responsive 'to an increase ordecrease in the quantity of the gas when the static or normal pressureof th gas is increased or decreased.- Therefore, if a pressure changeoccurs in the flowing stream to vary the quantity' afp-gas flowingVthrough the apparatus, an inaccurate feeding of the odorant" into theflow line occurs.

generally used as odorants, have vapor-prese,y

Further, the liquids,

sures which vary'according to their temperature and pressureconditionslnd-,alsd the ilow characteristics of said liquidsvary'accordingto their viscosity and temperature. In the usual typewofodorizing apparatus, no provision has been--niadejI for compensating forthese variables, with theLv` result that said variables 'affect theoperationto produce inaccurate feeding or introduction of the" liquidinto the line.

It is, therefore, one object of this' invention to provide an improvedmeans for introducing a liquid into a flowing gas stream in quantities`directly proportional to the quantity of gas flow: said method being.unaffected by variations in pressure in the flow line, or variations inviscos-A ity, temperature or pressure of the 1iqui`d,`where by anaccurate and predetermined amount of liquid per million cubic'feet `ofgas may be introduced intothe flowing gas stream.

An important object of the invention is to provide an improved means forintroducing a liquid odorant into a flowing gas stream which includes,

setting up a pressure diierential in the stream,

tion of vthe flowing gas isby-passed around aV pressure diierentialpressure Vproducing element ,in ,the main gas stream and is vdirectedthrough a suitable meter to operate said meter, together with means forutilizing the meter to drive a feed pump which introduces a liquidodorant into the main gas stream; the arrangement actuating the Qvarious positions of the Ypump* mechanism,

pump in direct proportion to the volume of gas ilowing through the line.e

A, further object of the invention is to provide an improved apparatus,of the character .de-

scribed, wherein a variable orifice is disposed the pressure of the gasflowing through` the main ,flow line may be, readily compensated for tochange the outputof the liquid pump'and to maintain thev introduction ofthe quantity yof liquid directly proportional to the `volume of gasflowing through the main line; the orifice being arranged to be eithermanually or automatically operated.

Still another object of the invention is to provide an improved feedpump for an odorizing apparatus which is so constructed that it isunaffected by temperature and pressure conditions,

whereby it will deliver a predetermined quantity of volume of liquidduring each cycle of opera- A particular object of the invention is "toprovide an` improved apparatus, of thecharacter described, wherein apressure differential is (created in the flowing gas stream and aby-pass line conducts a portion `-4of the gas around the point of suchdifferential, `said byfpass also having apressure differential set uptherein which is directly 'proportional to the` pressure differential inthemain stream, the"gas flowing through the inf-pass being utilized todrive Ia liquid odorant pump .which'is readily adjustable to inject apredetermined quantity of liquid Aodorant into vthe mainstream; thearrangement making it possible toV readily compensate. for variations inthe pressure ofthe main gas stream, either by changing the flow oriilcein the by-pass line or by varying the output of the pump.

lA construction designed to carry out the invention will' behereinafterdescribed, together with other features of` the invention.

The invention willbe more readily understood from a readinggpf the;following4 specification vand byreferencetdthe accompanying drawings,

in Awhich an example of the invention is shown,

.and wherein:

Figure 1 is a view partly in elevation and partly in section of anodorizing apparatus, constructed in accordance with the invention,Figure. 2 is a. transverse, vertical, 4sectional view, taken on the line2-2 of Figure ,1,

Figure 3 is a. plan View of the receptacle' or tank which receives theliquid odorantrand whic has the liquid pump mounted, therein,

`Figure 4 is a longitudinal,l` vertical, sectional view, takenon theline 4 4 of Figure 3, I

Figure 5 is' a vertical, sectional view, taken on theyline 5 6 of Figure3, and illustrating the 4 pipe I6, which extendsthrough vthe; opening 43Figure l.

Figure 6' is a transverse, vertical, sectional view, taken on the line6-1-6 of -Figure 3,

Figure -'7 .is aA transverse, vertical, sectional view, taken on theline I-'I of Figure 4,

Figure 8 is a transverse, vertical, sectional view, taken through theprecision valve which is connected in the by-pas's line, said valvebeingv manually operatedfand Figure 9' is a transverse, vertical,sectional view of an automatically operated precision valve.

In the drawings, the numeral I designates a flow line or pipe, throughwhich the gas is flowing. An orice plate II, having ari'axial orice I2therein, is mounted inthe flow line I0 and, as is clearly shown inFigure 1, the plate is conned between the ends of a'pair of flangedcollars I3 and Il, said collars being secured to the extremities ofadjacent pipe sections which make up the flow line. The outwardlydirected ilanges of the collars I3 and I4 abut oppositesides of theorifice plate II and suitable bolts I5 pass through said flanges andthrough the peripheral portion of the plate to securely mount said platewithin the flow line. The'provision of the reduced orifice I2 in the owstream sets up a pres.- sure differential across the plate and thispressure differential is, of course, dependentupon, the size of theorice as compared to the inner diameter of the ow line` I0,--v L Forby-passing al-portion-v A'ofi' the flowing gas around ythe oriilceplate' I-I, ahy-.pass pipe Iii-has its .lower endfconnected`into"aradial-porti1lI='I,l which is formed in" the flangeof =thecollar-I3.' The y--upper '1:' ortion Vorftherpip'e `extends-throughanopening I8 which is lformed in a base plate I9 and the Aextreme `.upperend of` saidillbypass pipe isv connected tof-a diaphragmV type displace;

mentl meter 20. The meter is'ofrthe usual con-l struction: andmay 1 bepurchased on theY :open'v market, and it isi noti-believedinecessaryktode-e scribe said meter in detail; The-'meteismounted within a housingorfcasin'g V2 It? which is formed.v with a lflange. 221011, itsv'1ower.end; I This verlange: overlies `the peripheralvportion 'ofthe.base :platel I9. and is secured theretol by suitable ybolts 23..and-rnutsk 24.- A gasket` 25 isinterposed between -the` flange 22 and-thebase plate;whereby/1a.v fluid-1;:- tight seal ,.isfefectedwat the,.ioint.r The'by-passi` 50 inthe base platey is preferably,.weldedforfotherwise .securedto-said plate, asis illustrat d inf-lThesas which ,iSfQwina .thru'hliha une' ,u'may passgupwareiy through'are nlnlns. l1 and into the lay-pass pipe' `ityirrlllfi bien" 1t flowsiHtOihC'meWr 20,?. A Suitable, aedfifell'' 26 maybe'connected in'thepipe I6 iinme'diate'lyy above thelowerend" thereof, wherebyif desiredshut orf. VThe gasvwhich ows 'upwardly thro'ughf the by-pass line I6passes through the'fmeter 1201.1 and then ilows into a return fpipe' 21,.which pipe has itsvupper end'connectedf'tothe outlet side'of 'Ythemeter 20. The 'pipe 21rextends downwardly through .the housing 2|Aand-through an opening 28 formed in the base platerl. Thesplpeis'suit-f ably welded, or otherwise` secured, toc'lthetbase plate and thelower endfof said pipe :has connec-l tion' with an opening -29 which'isformed ini-ones;y ofV the connecting collars I4. Thusyit .willfibe seenthatthe gas which :flows upwardlyfin the; by-passpipe IGpasses through;the meter!! and is thenfreturnedtothe main flow linev I O through thepipe 211,e such return being; on Athe,opposite 75:

side of the o rice plate II. In this manner, a portion of the gas fromthe main ow line is bypassed around the orifice plate II, beingconducted through the meter 20. A suitable hand valve 30 maybe connectedin the lower portion of the pipe 21, whereby flow therethrough may beshut olf.

, For creating a pressure differential within the *Y by-pass pipe I6,'aprecision valve 3I is connected said by-pass line above the manuallyoperated control valve 26 (Figure 1). The valve is clearly shown inFigure 8 and includes a valve body 32 which is provided with atransverse partition or deck 33 therein. The deck is formed with anopening 34 therein, and a cylindrical valve member or plunger 35 ismovable within said opening.

collar 38 which iswpreferably formed integral' with -the valveI body. LAsuitable' stufng box 39 surrounds the.' valve stem soas=to lpreventleakage around the threads-thereof. The upper-end of the zstemprojectsfrom thestumng'box and has asuita'blehandwheel 40 thereon,whereby manual manipulation of the Avalve isrfacilitated A n indi-Ycator'disk- 4I 'is'secured tothe stem'and, as said valveplunger -35ismovedhvertically within the valve body,the1valve diskA travelsvertically with relationto an indicator arm-2,which may carry suitablegraduations or indications, tolindicate the kpositionof `the valveplunger. i

With the valve'in the position'shown ixiFigure ythe'extremeupper end ofthe inverted V-notch or slotl'ls aboveV the top of thedeck 33 andtherefore arestricted ow past the' valve seat isV permitted. If thevalve stem is rotated'to raisel the =valveplunger 35, a' greater area ofthe notch 36 willbe' exposed above the deck; whereby the sizeof? theorice isincreased. Similarly, if the stemis. rotated inanopp'ositedirection, and the plunger is s moved downwardly, I then the ilowthrough :the-valve' ybody will beshut off. With n thisarrangement,v itispossible to vary'the size of the oriflce'rthrough which `the by-passedgasv flowswnOf course,` the size of the orice will control the quantity7off` gas andwill' also 4set up a shown in Figure 2 and said shaft isordinarily connected-with an indicator (notshown) which traverses a dial(not shown). `The dial is ordinarilyV mounted within a dial recess- 44provided'- `vat onejside ofthe .meter housing. YIn carrying outy theLpresent invention, the usualdial and indicator` larerexnoved from therecess and a plateoverlies Vsaid recess,-being secured to the frontofnthe meter.l housing. .The baseV of` the frecessls Aformed;withanOpening 46 within which diaphragm type displacement metergasgflowingfthrough said meter.V The shaft is4 stub shaft 48 is alsorotated. A sprocket 49' is keyed or otherwise secured onto the outer endof the stub shaft 48, whereby said sprocket is rotated when the shaft 43is rotated by the gas flowing through said meter.

A liquid container or receptacle 50, which is.

adapted to receive the liquid odorant which is to be introduced into themain line I0, is mounted within the casing 2| above the meter 20, saidreceptacle being supported by suitable brackets 5| which are secured touprights or posts 52 mounted on the top of the meter housing 20. Thetank is substantially rectangular in shape and has a liquid pumpPmounted therein. The pump is adapted to pick up the liquid in thereceptacle 50 and discharge the same into a compartment 53 which isformed at one side of the receptacle. The compartment 53 has a baille 54located near its discharge end and, as is clearly shown in Figure 6,said `baille is provided with a plurality of graduated openings 55 whichare disposed vertically therein and which are grad' ually enlargedtoward the upper end of said baille. 'I'he purpose of these openings isto provide an evenfiow of liquid from the compartment 53, as will behereinafter explained. i 'Ihe lower end of the 'compartment communicatesthrough a discharge tube 55 with the upper end of the` return pipe 21,whereby the liquid which is pickedup by the pump P and directed into thecompartment'53 flows `into the return pipe and then into the main flowline I0.

'I'he construction of the liquid pump P is clearly shown in Figures 2, 4and 5 and includes a curved tube 51, which has its outer end open.

The inner end of thel tube is secured to a sleeve t 53 and communicateswith the interior of said sleeve through an opening 59. The sleeve 53surrounds a portion of a drive shaft 60 and said sleeve is welded, orotherwise secured, to the shaft so as to be rotatable therewith. Aradial arm 6| extends outwardly from the `sleeve 53 and has a weight 62adjustably secured thereto, whereby the weight counterbalances' the tube51 which is rotated when the shaft and sleeve are rotated.

The drive shaft 80 extends transversely across the interior of the upperportion of the receptacle 50 and has one end journaled in one side wallof said receptacle, while the opposite end of said shaft is journaled inthe side wall of the compartment 53 (Figure 2). which is journaled inthe side wall of the liquid container or receptacle 50 projectsoutwardly beyond said wall and has a sprocket 53 secured thereto. y Thissprocket is vertically alined with the drive sprocket 49' on the stubshaft 4l, which shaft is driven by the meter shaft 43, and the sprockets49' and 63 are connected by a suitable drive chain 64. .With thisarrangement, it will be manifest that the meter shaft 43, which isactuated by the gas flowing through the meter llfserves to drive thepump shaft 50. whereby the pump is operated in accordance with the gasflowing through the meter. It ismanifest that bychanging the ratio ofthe sprockets 4l' and 83 to each other,'the pump may be operated at anygiven speed for a vgiven amount of gas passing through the meter;-

As the drive shaft 50 is rotated, the pick-up tube 51` of the pump P(Figure 5) rotates in a counter-clockwise direction, whereby the openend of said tube dipsl downwardly into the liquid standing 'in the lowerend of the receptacle 50. Some of the liquid is thus picked up by thecurved tube 51 and, as said tube continues its rotation, said liquidhows downwardly through the tube and into the sleeve 58 which surroundsthe drive shaftil. From the sleeve, the liquid flows outwardly anddownwardly into the compartment 53, and then through the openings 55 inthe transverse baffle 54 of said compartment. From the compartment, theliquid is conducted through the tube 56 to the return pipe 21, and then.to the main flow line I0, through which the main gas stream is flowing.It will be manifest that the level of the liquidwithin the receptaclewill control the amount of liquid which the tube 51 picfks up upon eachrevolution. If the level is as shown in1 Figure 5 by the dotted line,then only a small amount or quantity of liquid 4is picked up on eachrevolution of the tube. However, if the level were raised, it is obviousthat 'I'hat end of the shaft a greater amount or quantity of liquid willbey picked up upon each revolution of said tube.

Therefore, by varying the liquid level within the' receptacle 50, it ispossible to vary the output of the pump, that is, it is possible tocontrol the amount of liquid discharged upon each revolution of the tube51. For preventing the liquid which,l

is picked up on the tube and which may accumulate on the outer surfaceof the tube from travelling along the drive shaft 50 and escaping pastthe side walls in which the endsV of the shaft are journaled, a pair ofbaiile plates 55 may be secured to the shaft 50 near the extremities.thereof.

For maintaining a desired liquid level within the receptacle 50, inorder to control the output of the pump P, a float 66 is provided. Thisfloat extends downwardly into the receptacle and is Y carried by athreaded stem 51. The stem is threaded through the outer end of apivotedv lever 58, which klever has a counterbalancing weight on itsopposite end. The lever is mounted on a pivot pin 10 which is securedwithin depending lugs 1i formed on then lower end of an inlet nozzle 12.'I'he inlet nozzle is secured to the upper end of the receptacle andoverlies the lever arm 68, as is clearly shown in Figures 3 and 4. Thenozzle is provided with a laterally directed passage 13 which has avalve seat 14 mounted at its inner end. A valve., member 15 is adaptedto engage the seat 14 and is movable vertically with relation thereto.The lower end of the valve member 15 rests on the lever arm 63 and, whensaid arm is in araised position, as shown in Figure 4, the valve isclosed. The position of the arm 58 is, of course. controlled by thefloat 56 carried by its outer end and, whenever the liquidlevel withinthe receptacle 50 falls, the lever arm is swung downwardly on its pivot10, whereby the valve member 15 is moved -away from its seat 14. Asexplained, the float stem v61 is adjustable within the lever arm andcarries an indicating disk 16 at its upper A end. This disk is movablevertically with relation-to an indicator bracket 11 which carriessuitable graduationsor indications thereon. The position of the disk,with relation to the indicator 11,` denotes the position of the float55, with the result that the level at which the liquid is held ormaintained within the receptacle may be readily determined.

The nozzle 12 has its outer end connected by means of a tube 18 withthelower end of a stand pipe 19, which pipe is secured to a storage tank80. The lower portion of the stand pipe 19 is connected through a pipe8| with the lower end of the tank `80 and'/ a suitable hand valve 82 isconnected in the pipe 8|. The upper portion of the stand pipe 18 alsohas communication through a short pipe 83 with the upper end of theliquid storage tank 80. A tube 84 also establishes communication betweenthe extreme upper end of the pipe 19 and the upper end -of'the casing2|, which houses the meter and pump apparatus. A suitable gauge glass 85may be mounted'at one side of the stand 'pipe 19 to denote the liquidlevel within the tank' 80.

The liquid from the storage tank 80 ows through the pipe 8|,'into thelower portion of the stand pipe 19 and then through the tube 18 into thenozzle 12. When the valve 15 is unseated, this liquid may enter thereceptacle 50 to maintain the liquid level Within said receptacle.-Since the ulper end of the receptacle 50 is op'en to the interior oflthe casing 2|, it is .necessary that the pressure within the casing 2|be equalized with the pressure in the liquid tank 80 to assure a ilowdownwardly through the tube 18. For this purpose, a vent opening 86 isformed in the extreme upper end of the return pipe 21, whereby gas whichhas passed through the meter and is ilowing through the return pipe mayescape into the casing 2|. Since the upper portion of the casing 2|communicates with the upper portion of the liquid tank through the tube84, stand pipe 19 and pipe-8e3,- it is manifest that the pressureswithin the casing 2| andthe tank 80 will be equalized at alltimes. Thiswill assure that va constant flow of liquid from the 1.

storage tank 80 to the inlet nozzle 12 will occur.

sure diierential across the /orice |2, a change occurs in thedifferential across the Valve 3 I, with the result that the pump isoperated at a diierent speed of rotation. Therefore, a different 5amount of liquid, in accordance with the change in volume, is deliveredto the flow line l and thus the provision of the valve in the by-passline I6 provides for the'apparatus automatically adjusting itself tocontinue to deliver the proper l0 quantity of liquid.

However, if the pressure in the flow line l0 varies from the initialworking pressure, for which' the oriilce plate has been installed andfor which the various adjustments have been i made, 'then the volumetricdisplacement through 2g suits'A in| avriation of the volumetricdisplacement through the meter. Such variation in the volumetricdisplacement of the meter 20 causes a change in the speed of the pump P,since said pump is driven directly from the meter. The

pressure variation in the inlet side of the line |0 has not affected thevolume of gas flowing through said line and, in order for the apparatusto operate efficiently, the pump must deliver the same amount of liquidto the line, regardless of the pressure. Thus, it willbe seen that whena lpressure variation occurs, a change in the speed of the Dump occursand, in order for eilicient operation, it is necessary at this time toeither speedup the pump P or increase the amount of liquid which thepump is delivering upon each stroke. As explained, the volumetricdisplacement through the meter 20 varies indirectly as` the' ratio ofthe 4actual working pressure to the initial pressure. In order tomaintain the volu- In the operation of the device, the apparatus 0 isadjusted so as to deliver a predetermined quantity of liquid .odorant tothe flowing gas stream per'a predetermined number-of cubic feet of gasflowing through said line. I1\'hese adjustments are made by properlyadjusting Ithe pre.- cision valve `3| and by xing theratio between thedrive sprockets 49 and 63, aswell as by. maintaining the liquid levelwithin the liquid receptacle 50, whereby the pump delivers apredetermined quantity ofJ liquid upon each revolution thereof. Forexample, supposing that 100,000 eubicffeetf'f'.free gas is flowing'through thelinevlll, then a fixed or predetermined pressurediilerentialacross the orice 2 is present. A portion oi the free gas is ilowingthrough the the pressure diierential across the orificellZ, is presentacross the valve 3|. 'I'he gas flows through the meter to rotate Atheshaft 43 and. thereby operate` the drive sprockets I9' andf53 since thevalve 3| has a pressure diierential thereacross, which is proportionalto the pres- 75 4 'metric displacement directly proportional to thequantity, it. is only necessary to adjust the preoisi'on valve 3| toincrease the size of the orifice in the by-pass line I6. When this isdone, the pump is maintained operating at its original 45 speed andtherefore delivers the same amount of liquid to the flow line.

Of course, it would be possible to leave the valve 3| in its sameposition and to change the liquid level in thefreceptacle 50. In suchinstance, the speed of the pump would be varied because of the change inpressure of the gas, as has been explained, but the change in thevliquid level would cause the pump to deliver more or less liquid uponeach operation or revolution to compensate for the kchanged condition.Thus, j by-pass line |8 and, therefore, a predetermined pressurediierential, which is vproportionate to it will be seen. that theapparatus will constantly deliver a predetermined quantity of liquid tothe ilow line, regardless of the pressure change in said line.

In order to more fully explain the operation and the principle oi' theimproved apparatus, the following is submitted,` wherein:

Q1 equals cubic feet of gas per hour owing throughline I0 throughby-pass I6 C1 equals coeilicient of oriilce |2 -C2 equals coeillcie'ntof. oricein valve 3| P equals absolute pressure A equals atmosphericpressure D equals differential pressure across oriilce V equalsvolumetric displacement in cubic ieet in meter` 20. e The iiow of gaspassing through the orifice |2 Q2 equals cubic feet of gas --f'per'hourowing Y f become clogged or stopped up.

the displacement meter conforms to the! formula Q2=VP/A. The by-passedgas flows through both the precision valv.` 3| and the displacementmeter 20 so that C2=\/D P=VP/A. The maximum hourly rate of displacementor V through the meter is limited and to maintain V constant to maintainthe speed of the pump constant, when the pressure P increases, it isnecessary to increase C2 (the coeilicient of orifice in valve 3|)according to the square root of the absolute pressure. 'Ihis isnecessary to maintain V (volumetric displacement in meter)- in directproportion to Q1 (quantity of gas flowing through main line I). Thus,the setting of the precision valve 3| is a function of the square rootof the absolute pressure. When the pressure varies from theV initialedpressure, for which the apparatus is adjusted, then V, or the volumetricdisplacement through the meter varies indirectly as the ratio of theactual or new pressure to the initial or base pressure. When thisoccurs, in order to maintain V directly proportional to Q1, it is alsonecessary to adjust the valve 3| to change its orifice (C2) and thuschange the quantity of gas (Q2) flowing through the bypass and meter,directly in proportion to the ratio o! the change in pressures, By soadjusting the valve 3|, the liquid is delivered in direct proportion tothe gas -ilowing through the line l0.

It is noted that if the pressure in the by-pass exceeds approximately 50pounds gauge pressure, the pressure drop which occurs across the meteris excessive and has been found to result in excessive wear on themeter. Therefore, when pressures exceeding 50 pounds are encountered, itis desirable to adjust the output of the liquid pump P rather thanfurther adjust the precision valve. The adjustment of the pump will behereinafter more fully explained.

From the foregoing, it will be seen that the device is readily adjustedto take care of any change in pressure condition. Accurate odorizationis had at any rate of iiow and the apparatus does not include any smalloriiices which may The pump P s constructed so that the curved tube dipsdown into the liquid upon each revolution and, according to the liquidlevel, picks up a predetermined amount of liquid upon each revolution.This amount or quantity of liquid is definitely fixed and is positivelydelivered to the ow line. The construction of the pump is such thattemperature or pressure conditions do not affect the amount ofliquiddelivered by said pump. Thus, no error due to the temperature or theviscosity of the liquid odorant can occur. Although any liquid storagetank can be employed for delivering the liquid odorant to the receptacle50, the tank shown in Figure 1 and described herein has been found mostsuitable. The arrangement of the tank and its associate parts makes itpossible to accurately test the volume or `quantity ofodorant which isbeing fed into the iiow line I0. Referring to Figure 1, it is pointedout that when the valve 82 is open, the liquid flows directly from thetank through the line 18 and through the inlet nozzle 12 to thereceptacle 50. When it is desired'to test for the amount of liquid beingdirected into the ow line,

`the valve 82 is closed, with the result that the liquid flows from thestand pipe 19 downwardly through the tube 18. The amount of liquidwithin the stand pipe is registered by the gauge 85 and, through the,use of a test scale (not shown), the volume ci.' liquid owing from thestand pipe 'I9 can be read in thousandths of a gallon. 'I'he thousandthsoi a gallon lso indicated, as being used' during any speciiled period oftime, can then be compared tothe reading of a Vmeter which is measuringthe total gas -iiow for the same period4 of time through the line I0and, thus, an accurate indication of the volume of liquid odorant permillion cubic reet of gas, can readilybehad. j

In Figure 9, an automatic type of precision valve Il' is disclosed. Thisvalve is substituted for the manually operated valve 3| and is connectedin the by-passline i6, the flow through this valve being in thevdirectionof the arrows in Figure 9. In this form, the valve stem 3l' hasits upperend connected to aflexible bellows 90, which is of apredetermined resistance. A lever 9| overlies the bellows 9|) and hasone end pivoted to an arm 92, which .has its lower endmounted 0n thevalve body. YAn adjusting screw 93 is threaded throughA the lever andhas its lower end engaging the'top of the bellows 90. The outer end ofthe lever is arrangedto be connected by means of a spring 94 with anextension 3|a, which is formed on the valve body. It is noted that thespring may be connected to the lever and to the extension at variouspositions with relation to the pivot 'of the lever, whereby it willexert a predetermined force. Obviously, since the screw 93 engages thebellows, the tension or pressure of the spring 94 is vconstantlyexerting downwardly on the bellows to urge the valve member 35 to itsclosed position.

The static pressurev or the pressure of the gas flowing through the mainline l0 is exerted against the underside of the valve member 35 and the'spring and lever are so adjustedv that a predetermined size orice ispresent under predetermined pressure conditions.4 IfV the pressure ofthe flowing gas should decrease, then the spring will immediately pullthe lever downwardly to further reduce the orifice; similarly, if thepressure below the valve increasesthen the valve is raised to increasethe oriilce and take care of the pressure change. vThe operation of theapparatus when the automatic precision valve 3|' is employed is exactlythe same as hereinbefore described. However, the use of this valve makesthe adjustment of theoriiice automatic iny accordance with the pressurechanges. l

The foregoing description of the invention is explanatory thereof andvarious changesinvthe size, shape and materials, as well as in the'details of the illustrated constructionmaybe made, within the scope ofthe appended claims, without departing from the spirit of the invention.

vWhat we claim and desire to secure by Letters Patent is:

1. An apparatus for introducing liquid into a flowingy gas streamincluding, a main flow line through which the gas stream is conducted, a

' restriction in said line for setting up a pressure stream, and meansfor utilizing the by-passing gas to actuate the liquid pump, whereby thequantity I liquid introduced is proportional to the volume of gasil'owing through the line.

2. An apparatus for introducing liquid into a flowing gas streamincluding, a main ilow line through which the gas stream is conducted, arestriction in said line forv` setting up a pressure diierential in theline, such differential being across the restriction, a by-passconductor for bypassing a portion of the gas around the restriction inthe main flow line, a variable restriction in the by-pass conductorwhereby a pressure differential proportional to the diierential in themain line is set up in said conductor, a liquid pump havingcommunication with the main line for introducing a liquid into theilowing gas stream, means ior utilizing the by-passing gas to actuatethe liquid pump, whereby the quantity of liquid introduced isproportional to the volume of gas 'flowing through the line, and meansfor changing the size of the restriction in the'by-pass conductor tovary the ilow through said conductor and thereby compensate for avariation in pressure of the ilowing gas to maintain the introduction ofliquid proportional to the volume of gas flowing through the main line.

3. An apparatus for introducing liquid into a flowing gas streamincluding, a main ow line through which the gas stream is conducted, arestriction in said line for setting up a pressure diilerential in theline, such differential being across the restriction, a bypass conductori'or bypassing a portion of the gasaround the restriction in the mainilow line, a variable restriction in th by-pass conductor whereby apressure differential proportional to the differential in the main lineis set up in said conductor, a liquid pump having communication with themain line for introducing a liquid into the owing gas stream, said pumpbeing adjustable so that its output may be varied, and means forutilizing the by-passing gas to actuate the liquid pump, whereby thequantity of liquid introduced is proportional to the volume of gasflowing through the line.

4. An apparatus for introducing liquid into a ilowing gas streamincluding, a main now line through which the gas stream is conducted,arestriction in said line i'or Asetting up a pressure dii' ferential inthe line, such differential being across the restriction, a by-passconductor for by-passing a portion of the gas around the restriction inthe main ow line, a variable restriction in the by-pass conductorwhereby a pressure differential proportional to the differential in themain line is set up in said conductor, a liquid pump havingcommunication with the main line `for introducing a liquid into theilowing gas stream, said pump being adjustable so that its output may bevaried, means for utilising the by-passing gas to actuate the liquidpump, whereby the quantityof liquid introduced is proportional to thevolume oi' gas owing through the line, and means for varying the outputof the pump to compensate for a variation in pressure of the flowinggas, whereby the introduction of liquid is maintained proportional tothe volume of gas flowing through the main line.

5. An apparatus for introducing liquid into a flowing gas streamincluding, a Imain flow line through which the gas stream is conducted,a restriction in said line for setting up a pressure di!- i'erential inthe line, such diilerential being across the restriction, a by-passconductor for by-passing a portion of the gas around the restriction inthe main flow line, a variable restriction in the by-pass conductorwhereby a pressure diilerential proportional to the diilierential in themain line is set up in said conductor, a liquid pump'havingcommunication with the main line for introducing a liquid into theilowing gas stream, means for utilizing the by-passing gas to actuatethe liquid pump, whereby the quantity of liquid introduced isproportional to the volume of gas ilowing through the line, means forchanging the size of the restriction in the by-pass conductor to varythe ilow through said conductor and thereby compensate for a variationin pressure of the flowing gas to maintain the introduction of liquidproportional to the volume of gas ilowing through the main line, andmeans for varying the output of the liquidY pump to further compensatefor pressure variation in the ilowing -gas stream. Y

6. An apparatus for introducing liquid into a ilowing gas streamincluding, a main flow line through which the gas stream is conducted, arestriction in said line for setting up a pressure diilerential in theline, such diilerential being across the restriction, a by-passconductor for by-passing a portion o1' the gas around the restriction inthe main flow line, a variable restriction in the by-pass conductorwhereby a pressure diierential proportional to the differential in themain line is set up in said conductor, a liquid pump havingcommunication with the main line for introducing a liquid into theflowing gas stream, means for utilizing the by-passing gasto actuate theliquid pump, whereby the quantity oi' liquid introduced is proportionalto the volume of gas flowing through the line, and means automaticallyoperable by the pressure of the ilowing gas for changing the size o! therestriction in the byfpass conductor to vary the ilow through saidconductor and thereby cornpensate for a variation in pressure of theilowing gasto maintain the introduction oi liquid proportional to thevolume oi' gas flowing through the main line. Y

7. An apparatus for introducing liquid into a ilowing gas streamincluding, a main flow line through which the gas stream is conducted, arestriction in said line for setting up a pressure diderential in theline, such differential being across the restriction, a by-passconductor for by-passing a, portion of the gas around the restriction inthe main flow line, a. variable restriction in the by-pass conductorwhereby a pressure diil'erential proportional to the diilerential in themain line is set up in said conductor, a liquid pump comprising a liquidreceptacle having a rotatable tubular element therein, means within thereceptacle for maintaining a predetermined liquid level in saidreceptacle, whereby the tubular element picks up a predeterminedquantity of liquid upon each revolution, means for conducting the liquidfrom said element to the main flow line, and means for utilizing the gasilowing through the by-pass conductor for actuating the liquid pump.

8. An apparatus for introducing liquid into a flowing gas streamincluding, a main tlow line through which the gas stream is conducted, arestriction in said line for setting up a pressure differential in theline, such differential being across the restriction, a by-passconductor forby-passing la portion of the gas around the restriction inthe main flow line, a variable restriction in the by-pass conductorwhereby a pressure diilerential proportional to the diil'erential in themain line is set up in said conductor, a liquid pump comprising a liquidreceptacle having a. rotatable tubular element therein, means within thereceptacle for maintaining a predetermined liquid level in saidreceptacle, whereby the tubular element picks up a predeterminedquantity of liquid upon each revolution, means for conducting the liquidfrom said element to the main iiow line, a. metering device connected inthe by-pass conductor and actuated by the gas ilowing through saidconductor, and means for operatively connecting the metering device tothe pump whereby the latter is driven by said device.

9. An apparatus for introducing liquid into a flowing gas streamincluding, a main flow line through which the gas stream is conducted, arestriction in said line for setting up a pressure differential in theline, such differential being across the restriction, a by-passconductor for by-passing a portion of the gas around the restriction, ameter connected in the by-pass conductor and operated by the gas ilowingtherethrough, a liquid pump for introducing a liquid into the 'main ilowline, and means for operatively connecting the meter and the pump,whereby the latter is driven by said-meter and the liquid is introducedinto the main line in proportion to the volume of gas flowing there#through. DONALD A. SILLERS. ALEXANDER CLARKE.

